The TASK_MAX_OUTPUT_LENGTH environment variable was dropped from the list of recognized/passthrough settings.
The function that computes the maximum characters allowed for task output no longer reads a taskOutputMaxChars setting; it now derives the limit from the current output host/target instead.
Why
This consolidates reading background task output onto the Read tool instead of a separate TaskOutput tool, and moves the output-length limit from a fixed global setting to something derived from where the output is being read.
The entry above is what we published on the day. These lines were added later, as Anthropic's own pages caught up, and they sit beside the original rather than replacing it.
Confirmed sinceAnthropic's documentation has since written up TaskOutput, on Environment variables.| `TASK_MAX_OUTPUT_LENGTH` | Removed in v2.1.277 and now a no-op, together with the `TaskOutput` tool it sized. Previously set the maximum number of characters of a [background task's](/docs/en/tools-reference#background-commands) output t…env-varssee the edit
How sure we are
Something disagreesSomething we can check disagrees with this entry, or the writer said they could not settle it.
The writer flagged doubtThe finding does not say what effect losing access to TaskOutput from this specific tool set has for a user in practice.
Anthropic's documentation agreesAnthropic's documentation has since written up TaskOutput, on Environment variables.
